The present invention relates to a mentod of treating combination defectiveness in combinatorial weighing or counting. More particularly, it relates to a method of treating combination defectiveness, which does not provide a combination which satisfies a set value in combinatorial weighing or counting, by increasing or decreasing the amounts of articles in one or more of weighing machines, to enable recomputations to be performed without stopping the machine or machines.
By combinatorial weighing is meant a mode of weighing in which when it is desired to obtain a set of articles which has a desired weight, articles are dividedly weighed in slightly varying separate amounts by n weighing machines, combinations of the thus found weights are computed, a combination which conforms to a set weight is selected from the computed combinations, and the weighing machines corresponding to the selected combination are caused to discharge their contents, thereby providing a set of articles which has the set weight. By combinatorial counting is meant a mode of counting in which when it is desired to obtain a desired number of particular articles, articles are dividedly weighed in slightly varying separate amounts by n weighing machines, each of the thus found weights is divided by the weight of a single article to find the number of articles in each weighing machine, combinations of the numbers are computed, a combination which conforms to a set number is selected from the computed combinations, and the weighing machines corresponding to the selected combination are caused to discharge their contents, thereby providing a set of articles having the set number.
In said combinatorial weighing or counting, in cases where it is found after combinatorial computations that there is no combination which satisfies set values, such as upper and lower weight limits, there has heretofore been no means to automatically remedy the situation, the only measures that can be taken being to give an alarm as by a buzzer or to stop the machines.
To give an example of treatment of combination defectiveness in combinatorial weighing, in cases where of the combinations obtained by combinatorial computations, the one which is the nearest to the set weight is not between the upper and lower weight limits, an alarm is given by means of a buzzer or a lamp to draw the operator's attention to inhibit discharge of articles from weighing machines. In this case, however, each time combination defectiveness is found, the weighing operation has to be interrupted, which is inconvenient and inefficient.
As another example of treatment of combination defectiveness, a combination of articles which is the nearest to a set weight is automatically discharged from weighing machines into a packaging machine each time, and if such discharged combination is not between the upper and lower weight limits, an alarm is given as by ringing a buzzer to draw the operator's attention. In this case, however, since the combination of articles which is the nearest to the set weight is discharged irrespective of whether it is between the upper and lower weight limits, the setting of the upper and lower weight limits is simply intended to inform the operator that the combination weight which is the nearest to the set weight is not between the upper ahd lower weight limits. Therefore, if the operator fails to notice the warning, the set of discharged articles which is not between the upper and lower weight limits will be packaged. Thus, these measures cannot be called desirable.